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Question
Find:
- equation of AB
- equation of CD
Solution
i. Slope of AB = `(3 - 4)/(3 - (-5)) = -1/8`
∴ Equation of AB is given by
`y - 4 = -1/8(x - (-5))`
8y – 32 = –(x + 5)
8y – 32 = –x – 5
x + 8y = 27
ii. AB and CD are perpendicular to each other.
Thus, product of their slope = –1
Slope of AB × Slope of CD = –1
`=>` Slope of CD = 8
Now, from graph we have coordinates of D = (–3, 0)
∴ Equation of line CD is given by
y – y1 = m(x – x1)
y – 0 = 8(x – 3)
y = 8(x + 3)
y = 8x + 24
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